The overall goal of the proposed research project is to better understand the role of psychological stress as a risk factor for the occurrence of subsequent cardiac events. Acute and chronic psychological stress has been shown to be a risk factor for cardiac events. More recently, acute psychological stress has been shown to produce myocardial ischemia in certain subsets of patients with coronary artery disease. Patients with myocardial ischemia have been shown to have a worse outcome than patients who do not have acute stress-induced myocardial ischemia precipitated in the laboratory. The overall goal of the proposed project is to study a broad spectrum of patients with coronary artery disease to accomplish two specific aims: 1. To test the hypothesis that coronary artery disease patients with the most abnormal peripheral artery responses to mental stress will develop myocardial ischemia in response to mental stress. 2. To test the hypothesis that patients with coronary artery disease and mental stress ischemia documented by sestamibi myocardial imaging with or without abnormal peripheral artery responses to mental stress will have a significantly worse prognosis for a) cardiovascular death, and b) adverse event rates than patients without mental stress ischemia. Abnormal responses will be defined as: finger plethysmography tracings (PAT) that decrease greater than 20 percent during mental stress. Adverse event rate will be defined as: a composite index of cardiovascular death, myocardial infarction, hospitalization for unstable angina, and bypass surgery or coronary angioplasty. The study will provide important new information on the independent predictive value of mental stress ischemia for adverse outcome in patients with coronary artery disease.